Visual Pigments: (a) General chemistry: source of color; model and modified pigments. (b) Function in visual excitation; rhodopsin as ion pore vs. ion combinant vs. enzyme. (c) Rhodopsin; shape, dimensions, tendency to polymerize. (d) Orientations and motions of rhodopsin in photoreceptor membranes and artificial films. (e) Synthesis of opsin (rhodopsin) in a cell-free system. (a), (d) and (e) are already in progress; (b) and (c) are planned. Comparative studies: all involving combinations of microanatomy, electrophysiology (spectral sensitivity, light and dark adaptation), and microspectrophotometry (hence biochemistry) of: (a) Vertebrate skin photoreceptors (frogs, other amphibia). (b) Polychaete worm eyes -- an almost untouched phylum. (c) Ventral parolfactory vesicles of squid. (d) Insect eyes: larval mosquito; noctural and diurnal moths. (e) Pineal (parietal) eyes of lizards. (b), (c) and (d) are in progress; (a) and perhaps (e) to begin at Woods Hole this summer (1974). Human vision: (a) Etiology of uniocular color blindness: somatic mutation vs. X-chromosome mosaicism. (b) Rod and cone function in retinal detachment and repair. (c) Visibility in the ultraviolet to 310 nm in normal and aphakic eyes. (d) Role of lens and maclar pigmentaton in visual acuity; dothey aid visual acuity by compensating for the (c) almost cmpleted; (b) not yet begun.